Jump to content
SAU Community

Recommended Posts

  • Replies 40
  • Created
  • Last Reply

Top Posters In This Topic

ok, i just rang my mechanic and told him if he thought it could be R&R. He said that its definetely my boost sensor that is causing the prob as he said even at 7psi the car was stuttering on the dyno.

Can R&R occur at 7psi.

Keep in mind this problem was occuring back when the car was stock standard.

Now I have a full 3inch exhaust from the turno, FMIC, pod filter and boost controller set at 7,10 & 12 psi.

Link to comment
https://www.sau.com.au/forums/topic/169507-rich-retard/#findComment-3132487
Share on other sites

Firstly, your ECU doesn't read your boost pressure. The boost sensor is only for your gauge on the dash. So its not your boost sensor thats the problem.

Could possibly be missfiring. R&R occurs when the ECU reads "too much airflow" coming through the airflow meter. It shouldn't happen at 7psi. 10psi+ I can understand it kicking in but not 7.

Your car probably has a missfire problem. Your spark plugs maybe the cause? or maybe your coilpacks.

Someone please correct me if you think otherwise.

Edited by KeyMakeR33
Link to comment
https://www.sau.com.au/forums/topic/169507-rich-retard/#findComment-3132528
Share on other sites

Rich and Retard is the definition given to Most people with lots of money E.G. Paris hilton.

If you are having issues where you lose complete power like you've hit a brick wall, it could be your AFM (Air Flow meter - which is the black box things just before your air filter.)

Ask your mechanic to take it off and clean the element in side it using electrical contact cleaner.

Link to comment
https://www.sau.com.au/forums/topic/169507-rich-retard/#findComment-3132580
Share on other sites

id be checking Spark Plugs (put new ones in for peace of mind - $100 for iridium heat range 6 gap 0.8), coil packs (check for gaps/cracks, do a search on how to quick fix them) and AFM (air flow meter - not sure how you can self test this - think you need a CONSULT hookup.). doesnt sound like r&r if it happens at 7 psi.

Link to comment
https://www.sau.com.au/forums/topic/169507-rich-retard/#findComment-3132589
Share on other sites

while we have this up on topic; i have a very basic idea on what the following terms mean, but for better understanding for others and myself; can someone please explain in detail what these mean:

- Pinging

- Retard

- Rich/Lean

:huh: CHEERS!

Link to comment
https://www.sau.com.au/forums/topic/169507-rich-retard/#findComment-3132599
Share on other sites

R&R occurs when the ECU reads "too much airflow" coming through the airflow meter. It shouldn't happen at 7psi. 10psi+ I can understand it kicking in but not 7.

Your car probably has a missfire problem. Your spark plugs maybe the cause? or maybe your coilpacks.

R&R is how the Nissan engineers made a fail-safe ceiling. They intended it to make around 240 crank hp. Bigger mass-flow represented by more boost allows the ECU to see higher than specified max values from the AFM.

It MAY be possible for the mass-flow to hit the factory-set ceiling if you have a free flowing inlet and exhaust. We don't know if it has a pod/FMIC/exhaust system upgrade. (EDIT: yes we do, didn't see the comment) Notice the problem is associated with colder conditions? Higher air density makes it easier for the engine to get the staggers. FWIW, mine did the same thing with just those changes, and running on stock boost.

Edited by Dale FZ1
Link to comment
https://www.sau.com.au/forums/topic/169507-rich-retard/#findComment-3132661
Share on other sites

R&R is how the Nissan engineers made a fail-safe ceiling. They intended it to make around 240 crank hp. Bigger mass-flow represented by more boost allows the ECU to see higher than specified max values from the AFM.

It MAY be possible for the mass-flow to hit the factory-set ceiling if you have a free flowing inlet and exhaust. We don't know if it has a pod/FMIC/exhaust system upgrade. (EDIT: yes we do, didn't see the comment) Notice the problem is associated with colder conditions? Higher air density makes it easier for the engine to get the staggers. FWIW, mine did the same thing with just those changes, and running on stock boost.

I agree with the colder air hence denser air conditions. And yes making the car breathe better can also be a big contributer.

Link to comment
https://www.sau.com.au/forums/topic/169507-rich-retard/#findComment-3132678
Share on other sites

I had a similar issue with my 33. Except it was happening on 10psi. I spent too much time and money on spark plugs, coils, etc. It turned out to be the AFM. R&R occurs when the AFM reads over 5 volts and the fuel maps hit the upper limit of their auto learning program. I would except it to occur more in cold weather as the air is heavier (dense) and the AFM can flow more air but will read higher on the same boost pressure. Hence why turbo cars run heaps better in cold weather as the intercooler is more efficient and the ambient air is cooler to start with.

The problem with the stock Skyline ECU's is they can't handle the big boost increases. Remember stock they run 5psi/7psi dual boost setup. The fuel maps can only auto adjust so much before they hit the "dangerous boost levels". When the Fuel maps hit the upper limit of their adjustable range the car will R&R. You can always tell a skyline that has had the boost turned up and exhaust etc as they blow black puffs at top RPM.

To fix this issue I would check the spark plugs, and if they seem fine, invest in an AFM interceptor, like the Jaycar Digital Fuel Adjuster or the Apexi SAFC II. Both will solve the issue if your plugs are good and will allow the car to be dyno tuned to a degree. When you replace your plugs don't bother with irridium ones they run too hot. I run cheap copper ones, about 4 bucks each and the car makes 220 bhp @ Wheels with a stock turbo on 12 psi. The only issue with the cheaper plugs is they replacing every 10000 kms, but I was replacing platnum plugs every 15K as the car was running too rich and carboning up my plugs.

Hope this helps.

Speed

Link to comment
https://www.sau.com.au/forums/topic/169507-rich-retard/#findComment-3132783
Share on other sites

  • 6 months later...

Hmm, thing is what's happening at 10psi+ on stock ECU isn't R&R, at 10psi the ECU is in serious danger mode that's Fuel Cut.

If you've ever tried to exceed 10psi on a stock ECU r33 SII, or about 12 absolute max on a SI you'll suddenly feel like you've hit a brick wall, boost will be cut instantly and it jerks the whole car very violently. First time it happens you'll probably wonder what the fk you just did to your car heh. Anyway that's when the ECU feels boost pressure getting dangerously close to stock turbo limits (at or going juuuust above 10psi for SII and r34gt-t, 12psi for R33 S1) the ECU goes boom and cuts the fuel supply which kills boost.

So yeah, that isn't R&R, that's fuel cut and it's much more immediate and severe than R&R - and needs to be cos the ECU uses it when you are at or just less than 2 psi from what is considered breaking point for the stock turbo (12psi for SII and R34, 14 for SI).

I'm sure you can imagine how fast an overboosting wide open throttle could build from 10psi to 12psi to 14 then boom...like maybe a second or two heh, if that.

R&R seems to be commonly confused with fuel cut, and I think if I had a dollar for everytime someone mistakenly messed with their AFM, spark plugs, coils and injectors to fix a "misfire" that was being induced on purpose by the ECU retarding the ignition timing because its factory settings cause it to misinterprete mild boost tweaking as rapidly approaching turbo destruction :D

R&R isn't as immediate or severe as FC but worse almost because it's very frequently misdiagnosed as a normal misfire where one of the spark plugs or ignition coils is missing its turn under high boost etc.

The situation can be caused by a faulty AFM, but you will never see R&R at the peak boost limit, only fuel cut, and likewise fuel cut couldn't be mistaken for a misfire in a million years.

R&R seems to be used in situations where the boost levels are not really even close to critical meltdown level, but the increasing boost curve is not following the boost settings the ECU expects it to, and should the curve be projected at a linear increasing rate - which to be on the safe side is what the ECU has to assume - that if something is not done it would cause potentially serious damage in a few seconds time. To control it the ECU floods fuel (Rich) and delays (Retards) ignition timing briefly, and this often results in a misfire, while the oversupply of fuel combined with momentary lack of combustion and access to exhaust causes the turbo to be unable to continue producing power at any efficient level.

It can concievably happen on stock boost on very cold days etc when air is much easier to compress, and S2 and later GTS series ECU's are particularly twitchy because their lightweight nylon compression wheel spools faster than the S1 ceramic but it's also not expected to survive above 12psi while the ceramic is rated at 14.

Far more commonly it happens because of even minor overboosting on R33/34s, (not GT-Rs or 32s) and always well below the danger thresholds where you'll experience fuel cut at 10-12psi.

R33 GTS-Ts, R34 GT-Ts and stageas (and prob ceffies not sure) really frequently have R&R "misfire" and stuttering issues at about the 4-4.5k rev mark down low in the gear ratios during on-boost acceleration, where the boost prior to that rev point exceeds 5psi.

It's cuz people use bleed valves and such to increase boost at a linear level across the rev range...which is fine for some cars, but the models listed above have a factory 2 stage boost setup as standard which runs a lower boost very early on in the acceleration to make it a little more friendly in traffic, more torquey and less laggy at low speed. Within only a few seconds of firm acceleration the ECU gets ready to tell the solenoid to switch to it's full (stock 7psi) boost for the rest of the rev range.

So if you've manually boosted to 9psi, when it gets to that 4000-4500rpm range the ECU is expecting a 5psi setting to give way to a higher 7psi setting but is recieving data indicating a linear boost spike well above factory settings, not close enough to the absolute boost threshold to warrant a fuel cut but the projected curve indicates it'll get there fast.

So it uses R&R to prevent it spiking to dangerous levels. For a while you'll probably notice the sputtering every time you accelerate and not know what it is, after it has been doing it every time you accelerate for a while it will usually cause a misfire when it retards the ignition. You'll struggle a bit through that rev range without boost building or sustaining, at about 5k it'll build again and will generally stay solid til redline or you hit the factory cutoff threshold (and serves you a fuel cut) depending how boosted you are.

So yeah anyway, detailed explanation but there seem to be an absolute ton of people spending money on trying to fix elusive misfires that actually have nothing to do with faulty ignition components.

It's also easy to avoid - if you want to boost a little at stock you need to take the stock boost solinoid out of the boost control loop cos then the first boost stage won't be initiated, which means the ECU won't go "wtf?!" at the rising boost when its expecing a second stage, so it won't try and flood with fuel or retard the ignition.

There are a number of ways to eliminate the boosting safety precautions being executed too, but ultimately this all obviously relies on your ability to know what a reasonable level of boost is before you apply too much strain to stock internals.

More efficiently, as above posted get a remapped ECU for your setup, piggyback ECU or fuel regulating attachment like SAFC or e-manage.

I've seen pages upon pages of people posting about their R33/34 sputtering and misfiring and being told (in good faith) to go buy $600 splitfires or get a new O2 sensor etc etc. to fix a "misfire problem".

Even experienced mechanics (like mine who has hand built custom drag car engines with power levels that make ours look like scooters) who aren't used to skyline-specific issues almost always assume this is a misfire caused by a faulty spark plug, coil pack, injector, etc etc until it becomes an expensive, frustrating drama that never actually fixes the boost issue, at most hides it, until you one day put an aftermarket ECU or piggyback on and suddenly find out what kind of performance you didn't realise you were missing out on. : /

Often the "misfire" is really elusive and after spending hundreds on plugs and coils it's still there...other times the coils do cover it up, while in the background there's problems every time you accelerate and R&R kicks in, flooding your ignition system with fuel creating buildup that fouls spark plugs and leads to misfires....heh.

Point being, if there's stuttering/R&R and misfiring, fixing the misfiring is missing the point.

The misfiring is not the problem, it's a symptom of it.

Link to comment
https://www.sau.com.au/forums/topic/169507-rich-retard/#findComment-3511118
Share on other sites

wouldnt you think that cutting the fuel on a car would be very dangerous? or perhaps its ok if its completely cut rather than leaned out... hmmm

well i have a fuel cut defender (hey just realised you may be right lol) to stop the ecu spazzing out... which what i thought was R+R

running 14psi through stock turbo with stock coil packs and 1.0mm gap on platinums with no missing at all, been like that for a year so far.. 204kws with a fairly decent curve

ANYHOW, to the original poster you are getting whatever u want to call it and as others have said you need some sort of engine management to sort it out

btw mine couldnt even boost to 8psi without it crapping itself (that was with a full exhaust system only)

Link to comment
https://www.sau.com.au/forums/topic/169507-rich-retard/#findComment-3511220
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



×
×
  • Create New...